WASHINGTON • The US Navy will likely carry out another patrol within 12 nautical miles (22km) of artificial islands in the South China Sea before the end of the year, a US Navy official said.

The USS Lassen, a guided missile destroyer, last month sailed close to one of China's man-made islands in the Spratly Islands archipelago to underscore its rights under international law, drawing an angry rebuke from Beijing.

A US defence official said this month the Navy planned two or more patrols a quarter in the region as part of its plan to regularly exercise its rights under international law and remind China and others about its view.

The US Navy official said on Friday that the next patrol in the Spratly Islands archipelago would likely take place next month.

Two US B-52 bombers also flew near the artificial Chinese islands last week, in advance of US President Barack Obama's visit to the region this week to attend Asia-Pacific summits.

Mr Obama said on Friday that the disputed region would be a major focus of summit meetings among world leaders this weekend in the Malaysian capital of Kuala Lumpur.

China claims most of the South China Sea, through which over US$5 trillion (S$7.1 trillion) of trade passes every year. Vietnam, Malaysia, Brunei, the Philippines and Taiwan have rival claims.

Last Thursday, Mr Obama demanded that China halt land reclamation work which is turning seven reefs into artificial islands. China is building airfields and other facilities on some of them.

In a report published on the Chinese Defence Ministry's website last Thursday, China's top Admiral Wu Shengli said his forces have shown "enormous restraint" in the face of US provocations in the South China Sea, while warning that they stand ready to respond to repeated breaches of Chinese sovereignty.

Earlier this month, Senator John McCain, the Republican head of the Senate Armed Services Committee called on the Pentagon to clarify publicly the legal intent of last month's patrol.

REUTERS